External fixation of bone fractures



14, 1944- J. D. BERKE 2,362,741

EXTERNAL FIXATION OF BONE FRACTURES Filed Feb. 18. 1944 INVENTOR. JsephD. Berke %wym Patented Nov. 14,1944

UNITED STATES PATENT OFFICE EXTERNAL FIXATION OF BONE FRACTURES JosephD. Berke, New York, N. Y.

Application February 18, 1944, Serial No. 522,869

4 Claims.

This invention relates to bone surgery and more particularly to thetreatment of bone fractures.

The prime object of the invention centers about the provision of animproved method of and a splint for the external fixation of bonefractures.

In the current practice or technique of external fixation of bonefractures, threaded anchor pins are screwed into drill holes formed inthe bone fragments, and, after reducing the fracture and bringing thebone fragments into corrected relative position, the protruding ends ofthe anchor pins are bridged and joined or connected together by amechanical linkage splint comprising interconnected bars and clamps.This technique and the mechanical splints employed therewith suffer anumber of severe drawbacks, particularly where the fracture is on avisible part of the body and especially on a part difficult toimmobilize, such, for example, as the mandible or lower jaw of the head.The mechanical splint is difficult to use, requires exceptional surgicalskill to apply and adjust, and is, for such exposed parts of the body,markedly obtrusive and unsightly. The prime object of my presentinvention relates to improving the technique of external fixation ofbone fractures and to the provision of a novel splint that eliminatesall of these disadvantages.

In the method of my present invention, the anchor pins, preferably of aspecial and suited structure, are inserted into the bone fragments, and,after the fracture is reduced and the bone fragments are brought intocorrected relative position, the outwardly protruding ends of the anchorpins are encased in a shell mold containing a settable plastic material,and the plastic material is thereupon permitted to set and harden. Theshell mold, preferably made out of a plastic material, is preshaped tofit the body local to the fracture. In obviating the disadvantages ofthe external mechanical splints of prior practice, this unitingstructure, a splint is produced which does not undesirably project orprotrude from the body but which on the contrary is confined in volumeand locus to produce a not unattractive or unsightly appearance, thuscausing least disfigurement to the patient;

(4) The shell provides a smooth external surface completely surroundingthe wounded or affected part of the body, which may, therefore, at alltimes be kept thoroughly clean and aseptic; and

(5) The devices making up the splint are simple in design andconstruction and thus producible at a low manufacturing cost.

To the accomplishment of the foregoing objects and such other objects asmay hereinafter appear, my invention relates to the method and thesplint sought to be defined in the appended claims, described in thefollowing specification taken together with the accompanying drawing inwhich:

Fig. 1 is a perspective view showing the splint of the present inventionapplied for external fixation of a fracture of the mandible;

Fig. 2 is a view shown on an enlarged scale and taken in cross-sectionin the plane of the line 22 of Fig. 1;

Fig. 3 is a plan view with a part broken'away of the shell mold as usedfor the mandible fracture shown in Fig. 1;

Fig. 4 is a similar view of a shell mold preshaped to flt the chin andopposite lateral jaws of improved technique and appliance ischaracterand use and a strong, bone fragment uniting splint;

(3) The shell mold being preshaped to fit the body local to thefracture, and the shell and the patient;

Fig. 5 is a similar view of a shell mold preshaped to fit the chin ofthe patient;

Fig. 6 is a view thereof taken in cross-section in the plane of the line6-8 of Fig. 5;

Fig. 7 is a face view of a shell mold shaped to fit a mandible having adouble fracture on one side;

Fig. 8 is a view of another and smaller shell mold;

Fig. 9 is a perspective view of one form structure of the ancho pinsthat may be used for the splint;

Fig. 10 is a view of a modification thereof featuring a different formof head thereon; and

Fig. 11 is a perspective view of a modified form of anchor pin.

Referring now more in detail .to the drawing and having reference firstto Figs. 1 to 3 thereof, I show the technique or method and theappliance or splint of the invention applied to a,

double fracture of the mandible. As aforestated,

the contained plastic combining to form the pin the method and thesplint of the present invention is particularly advantageous when usedwith a visible part of the body and especially a part normally difllcultto immobilize, such, for exam le, as the mandible or lower Jaw of thehead. As applied for the treatment of such a fracture, the method of thepresent invention consists in inserting, exteriorly, the anchor pins 9,p into the bone fragments 20, 22 and 24 shown fractured in the tworegions 26 and 2., and, after reducing the fracture and bringing thebone fragments into their corrective relative position by any approvedmeans, encasing the outwardly protruding ends 80, III of the anchor'pinsin a shell mold s containing a settable plastic material 32, and in thenpermitting the plastic material 32 to set and harden. The shell mold sis preshaped to fit the body local to the fracture. This shell mold snot only encases all of the protruding parts 30, 30 of the anchor pins9. P. but forms a casing for the settable and set plastic material :2,the said shell fore, be handled with operative convenience. When theplaster of Paris or other contents sets to a hardened condition, boththe shell mold s and its plastic contents 32 form the mechanical bond orunion for the anchor pins, thus producing a strong bone fragment unitingsplint. The preferably irregular shape of the heads of the anchor pinsand also the provision of the internally projecting studs 38, 38preferably formed in the shellmold, help to securely anchor and unitetogether the anchor pins, the shell and the set plastic therein.

law fragments. The pins p, p are then screwed or skewered into the drillholes to effect the desired anchoring of these anchor pins to the shells and its contained set plastic 32. The protruding ends of the threadedpins p, p are preferably provided with enlarged heads which may be roundas shown in Fig. l or which may be given a special crossed or angularconfigurationsuch as shown by the heads 30', 3|! and 30 of the pins :2,p and p shown in Figs. 9, 10 and 11 of the drawing. When the anchor pinsor screws are inserted and anchored in the Jaw fragments, the fractureis reduced and the bone fragments are brought into corrective relativeposition by any approved means, as, for example, by wiring the teeth orby the use of suitable ligatures. The skin surface 32 may then betreated to render the same aseptic and the shell mold 3 previouslypreshaped to fit the affected part of the chin and jaw and into whichthe plaster of Paris or other plastic 32 has been placed, is thenapplied in position to encase all of the protruding parts of the pins 1p. a suitable membrane such, for example, as a sheet of Cellophane 36,being preferably placed over the skin and interposed between the sameand the edges of the shell opening as clearly depicted in Fig. 2 of thedrawing for preventing any contact of the plastic medium with the skinand also for effectively sealing the shell mold or casing. The thusapplied shell and contents is held in position until the plaster ofParis or other cement has set.

The resulting splint as best shown in Figs. 1 and 2 of the drawingpossesses the following characteristics:

(1) The shell mold with its contained plastic is readily manipulated andapplied and, therefore, requires no exceptional surgical skill for itseffective use.

(2) The shell mold s forms a casing for the contained plastic 32 in bothits unset and set condition. The plastic as it is formed and (3) Theshell mold preshaped to fit the body, and the shell andits containedplastic combining to form the uniting structure, a splint is producedwhich is confined .both in volume and locus producing a not unsightlyresult and thus causing the least disfigurement to the patient.

(4) The shell mold 8 completely surrounds the affected part of the bodyand particularly when made out of a'plastic material, such as from athermoplastic or thermosetting resin, provides a smooth and evenpolished surface which may at all times be kept thoroughly clean andaseptic.

(5) The shell mold s is preferably all enclosed except for the openingfor receiving the plaster of Paris fill and the anchor pins, the samebeing made preferably of a 'U-shaped cross-section as best shown in Fig.2 of the drawing. With this construction and in addition to :theadvantages above recited, there is provided an all enclosed shell moldclosed and sealed at its open side by the body of the patient. Thesplint, therefore, lends itself to keeping the affected part of the bodyin the aseptic state.

(6) The devices used to make up the splint are simple indesign andconstruction and are thus producible at a low manufacturing cost.

(7) Additional important advantages compared with the described priorart splint are that there is no movement of the parts of the splint onceapplied, there is no electrolytic aciton possible between the anchorpins or screws and the connecting bars as used in the prior art, thedevice permits of immediate application with simple implements andthereby helps reduce facial disfigurement caused by loss of bonefragments, the weight of the splint may be considerably reduced by theuse of a lightening filler such as asbestos rendered possible by theemployment of the encasing shell mold, etc.

As aforestated, the shell mold sis preferably made of a plastic materialpreshaped to fit the body which is local to the fracture. The shellmolds may be manufactured in different units to meet the differentconditions met with in operative service. This is illustrated by thedifferent forms or configurations which the shell molds may take asshown in Figs. 3 to 8 of the drawing. When made from a thermoplasticmaterial, the preshaped shell molds may be given their final shape bythe surgeon, by further heat treating the same. The configurations are,moreover, such that the surgeon may cut a mold to shape and fill in thecutaway sides with closing partitions. The forms shown in Figs. 3 to 8of the drawing are illustrative of what may be accomplished toeffectuate these ends.

The shell mold 8 shown in Figs. 1 to 3 is pre- I formed to fit the chinand one lateral law. The shell for this purpose comprises the generallyJ- shaped mold shown having a generally iJ-shaped section body 40 withits opposite ends closed by the walls 42 and 44. When made from athermopoured or placed into the shell mold may, there- 7| plasticmaterial, this shell may be further shaped to more closely fit thepatient's body, and if desired the end may be cut away such as the endsuitable partition will be used to replace the cutaway portion. Fig. 4of the drawing shows a-sheli mold s having the same general constructionas the shell mold s of Fig. 3, shaped, however, to fit the chin and bothlateral jaws of the mandible. Figs. 5 and 6 show a shell mold is ofsimilar construction, except that the same is made to fit the chin onlyof the body. Fig. 7 shows a shell mold s of similar construction, exceptthat it is made to fit the chin and a double fracture on one side of thejaw. Fig. 8 shows a smaller shell mold s designed to fit a smallfracture or one of limited area.

Reverting to Figs. 9, 10 and 11 of the drawing, it will be noted thatthe shanks oi' the anchor pins have diameters much smaller than theanchor pins used in the prior described technique.

This is made possible by virtue of the secure lodgment and anchoringobtained by the use of the shell mold s and its contained set plastic,the irregular shaped heads on the anchor screws contributing to thissecure lodgment and anchor ing effect. These smaller shanked anchor pinsalso enable a decided improvement in the operative technique of applyingand inserting the anchor screws into the bone fragments. According toprior technique and because of the large diametered anchor screws whichhad to be employed, drilling of the holes in the bone frag-.

merits had to be resorted to. With the use of the anchor pins employedin the technique of the present invention, it becomes possible toeliminate the drilling as an operative step. Accordhaving either thewall 42 or 44, in which event a ingly in the described technique. theanchor pins tures of my present invention and the splint thereof and themany advantages involved in the operative practice therewith will in themain be fully apparent from the above detailed description thereof. Itwill be further apparent v that whilefI have shown the invention appliedto the exterior fixation of a fracture of the mandible, this is givenbyway of exempliflcation and not by way oflimitation since the methodand appliance of the present invention are'generally adapted andintended for-external fixation of bone fractures. It will be furtherapparent that changes may be made in the method and in the applianceused without departing from the spirit of the invention defined in thefollowing claims.

I claim:

1. The method of external fixation of bone fractures which consists ininserting anchor pins into the bone fragments, and, after bringing thebone fragments into corrected relative position, encasing the outwardlyprotruding ends of the anchor pins in a shell mold containing a settableplastic material, and permitting said plastic material to set andharden.

2. The method of external fixation of bone fractures which consists ininserting anchor pins into the bone fragments, and, after bringing thebone fragments into corrected relative position, encasing the outwardlyprotruding ends of the anchor pins in a plastic shell mold containing asettabie plastic material, the said plastic shell mold being preshapedto fit the body local to said fracture, and permitting said plasticmaterial to set and harden.

3. The method of external fixation of bone fractures which consists ininserting headed anchor screws into the bone fragments, and, afterbringing the bone fragments into corrected relativeposition, encasingthe outwardly protruding heads and ends of the anchor pins in a shellmold containing a settable plastic material, and permitting said plasticmaterial to set and harden.

4. The method of external fixation of mandible bone fractures whichconsists in inserting anchor pins into the bone fragments of the jaw,and, after bringing the jaw bone fragments into corrected relativeposition, encasing the outwardly protruding ends of the anchor pins in ashell mold containing a settable plastic material, and permitting saidplastic material to set and harden.

- JOSEPI-I D. BERKE.

